Lean, mean fighting machines can classify some of the bosses in Chrono Trigger, but all of them can be classified as tough.  HP counts are approximated because Lucca's Sightscope can't read bosses.  Besides a picture of the boss and recommended team to face it, you can find out its location, time period, HP, Main attacks, Major Weaknesses, and a mini guide for handling the boss.
Boss Name: Heckran
Recommended Team: Crono, Lucca, and Marle
Time Period/Location: 1000 AD/Heckran Cave
Hit Points: 2100
EXP/Tech Points/Gold: 250/10/1500
Main Attacks: Yes Indeed!, Cyclone,
Major Weaknesses: Magic
Mini Guide: Heckran is the toughest boss you've faced so far because you are forced to rely completely on Magic.  As such, Crono, Lucca, and Marle make up the best team because they have actual magic spells.  Heckran will occasionally go into a "Brief Counter Attack Break", so hit him hard.  However, don't attack him when he says "Go ahead, Try and attack!"; spend that time healing your party.  Keep casting magic and keep up HP to defeat this Mystic devoted to Magus.
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Characters-    #1           #2          #3
Characters-    #1            #2        #3
Characters-    #1           #2        #3
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